U.S. Pat. Nos. 4,964,657, 7,316,429 and 7,201,382 and United States Patent Application No. 2003/0038481 describe press-connect plumbing fittings where multi-tooth grab-rings are used in addition to the pressed structural strength of the fitting. While the grab-ring does provide a portion of the pipe retention strength, there is also a component of the holding force caused by the intimate contact between the deformed fitting body and the tube.